Conventional lithography technology in the production of semiconductor devices includes double patterning technology with ArF immersion exposure, EUV lithography, and nano-imprint. In the conventional lithography technology, there are many problems associated with pattern miniaturization, such as increases in cost, a decrease in position accuracy of the pattern, and a decrease in throughput.
The application of directed self-assembly (DSA) methods to lithography technology is expected. DSA provides self-assembled phases of material generated by stable energy and therefore a pattern with high dimensional accuracy can be created. In particular, DSA provides a microphase separation of a macromolecule block copolymer that forms a periodic structure of various formations of several nanometers (nm) to several hundred nm wide by a simple coating and annealing process. The structure of the microphase material is changed into the various formations, such as spherical formations, pillar-shaped formations and a linear (layered) shape according to the composition ratio of the block copolymer. Hole, pillar, and the line patterns can be formed in various dimensions according to the molecular weight of the block copolymer, by selectively removing portions of the reacted copolymer in regions to create an etch mask from the reacted copolymer.
However, application of DSA to lithography techniques sometimes produces errors in the position of the patterns.